Subtract 18/84 from 1/21
1/21 - 18/84 is -1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
1/21 = 1 × 4/21 × 4 = 4/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
18/84 = 18 × 1/84 × 1 = 18/84 - Subtract the two like fractions:
4/84 - 18/84 = 4 - 18/84 = -14/84 - After reducing the fraction, the answer is -1/6
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